N.B. I no-longer have the originals, so I cannot upload a scanned version

The ink painting/ drawings show infection caused by downy mildew (oomycetes belonging to the Peronosporaceae).

Top: A pea seedling covered in white sporangiophores, shown as black outlines.

Middle: A bittercress stem, with two seed pods and one lateral leaf. The leaf is covered in sporangiophores.

Bottom: A seedling with three leaves arranged around a central bud. Two of the leaves are covered in sporangiophores.

The original photos were supplied by Prof. Mahmut Tör, who recommended I start drawing plant pathogens!